Before deciding any conclusion you need to know the merits and demerits of this framework. The bootstrap framework overall is good, but it also has some drawbacks. We will first discuss about the deficiencies and after that, we will cognize the strongpoints. So let's begin.

Low resolution of max width in full screen view

Bootstrap CSS container's max width is 1140px. Which is very small according to nowadays screen size. The screen size of a normal wide screen monitor is 1920 x 1080. And 1140px is very small according to 1920px. I think they need to add another container class with at least 1380px screen size.

Can't do pixel perfect work

This framework can't help you to make pixel perfect websites. Suppose you need a block of 978 pixels width, this framework will not create it for you. You have to write your own CSS mentioning the width measurement. Bootstrap can't create any kind of pixel-perfect blocks. I have heard in many places that, if you are using bootstrap, there is no need to learn CSS. In fact it is completely wrong.

Lots of unwanted classes

Bootstrap framework's main CSS file size is approximately 200kb. Which is too large according to a CSS file. You have to remove a lot of classes that you don't use. I personally don't like the navigation menu of Bootstrap, so I delete it. And I delete a lot of more classes that I don't need.

No proper details of CSS classes

You have to search in Google for details of each class of Bootstrap. They have no single page details like the Emmet cheat sheet. That's why you have to remember every class names. And in the beginning, you will find it difficult to remember every class names.

Very hard to work with other frameworks

If you want to use another framework with bootstrap, you may get some conflicts with the class names and default HTML elements. Almost every framework has 'container', 'row' and many more classes with the same name. The framework that will be linked in the last will dominate the others. So you have to work very cautiously.

So now let's discuss, what are the advantages of Bootstrap Framework.

Predefined CSS Classes

It has plenty of predefined CSS classes, which is necessary for website design. If you are not working with a Pixel Perfect website, then the Bootstrap framework can save your lots of time. You just have to remember the names of some classes and this CSS library will do the rest.

Cross-Browser compatibility

Bootstrap CSS classes are written with all prefixes. That means it will work in all Browsers. If you are working for older versions of IE, you may need some polyfill library like bootstrap-ie8. By the way… in its classes, all prefixes are written for all modern browsers.

Huge Popularity

Bootstrap framework is very popular compared to other frameworks. You will get lots of videos on YouTube and lots of tutorials on Google for this. And they also update it from time to time.

If you ask me whether I use it or not, I would like to say, yes I do. I delete a lot of classes that I don't need. The size of my bootstrap file that I use for designing is about 40kb.